Polyphenylene ethers (hereinafter, also referred to as “PPEs”) are advantageous in terms of heat resistance, low specific gravity, flame retardance, and so forth, and are used in office automation (OA), automotive, and various other applications. However, one issue relating to polyphenylene ethers is that they have inadequate resistance to oils, fats, and organic solvents due to being amorphous resins, which, to a certain extent, limits applications and environments in which polyphenylene ethers can be used.
For this reason, alloying of PPE resins with crystalline resins is being attempted in some applications with the aim of improving chemical resistance. However, a dramatic deterioration in impact resistance that occurs in a temperature region from the glass transition temperature of the crystalline resin to lower temperatures has been problematic.
In response to this problem, the addition of thermoplastic elastomers having low glass transition temperatures has been investigated with the aim of increasing low-temperature impact resistance (for example, PTL 1), but, at present, it has not been possible to obtain a resin composition having tracking resistance in addition to low-temperature impact resistance and chemical resistance.
Moreover, it is necessary to add a comparatively large amount of thermoplastic elastomer in order to impart a certain degree of impact resistance. This reduces rigidity of the resultant composition and limits applications thereof, and thus expansion to use in mechanism components and structures is currently difficult (for example, PTL 2 to 4).